Nonlinear muscles, passive viscoelasticity and body taper conspire to create neuromechanical phase lags in anguilliform swimmers.
Nonlinear muscles, passive viscoelasticity and body taper conspire to create neuromechanical phase lags in anguilliform swimmers.
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非线性肌肉，被动粘弹性和身体锥度共同创造了在驯武游泳者中产生神经力学相滞后。
DOI：
10.1371/journal.pcbi.1000157
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发表时间：
2008-08-29
影响因子：
4.3
通讯作者：
Holmes, P.
中科院分区：
文献类型：
--
作者：
McMillen, T.;Williams, T.;Holmes, P.
运动提供了神经肌肉系统、环境反作用力和感觉反馈之间合作的极好例子。作为一个程序的一部分，以了解运动的神经力学，在这里，我们构建了一个模型的anguilliform（鳗鱼样）游泳细长的鱼。建立在一个连续的机械表示的身体作为一个粘弹性杆，驱动的行波的首选曲率和流体动力学的反作用力，我们将一个新版本的钙释放和肌肉力量模型，拟合的数据从七鳃鳗Ichthyomyzon unicuspis，交互式生成的曲率波。我们使用该模型来研究肌肉激活的肌电波和身体曲率的机械波之间观察到的速度差异的来源，得出的结论是，这是由于被动的粘弹性和几何性质的身体和主动肌肉属性的组合。此外，我们发现，非线性力依赖于肌肉长度和缩短速度可能会减少所做的工作，由游泳肌肉在稳定游泳。在这篇文章中，我们开发了一个计算易处理的模型，如鳗鱼，七鳃鳗，水生蛇的动物游泳。该模型结合了运动神经元激活，肌肉动力学，脊髓和身体组织的被动弹性和阻尼，以及简化的流体动力学反作用力，从而使我们能够探索神经机械相互作用如何产生身体形状，并最终通过水运动。我们用它来调查一个有趣的实验观察的来源，在自由游动的鱼：波的曲率传播沿着身体滞后和旅行更慢，比肌电测量的肌肉激活波。通过选择性地“lesioning”组件的模型，我们推断，速度差，至少在这种类型的鱼，主要是由于被动粘弹性和身体的几何形状。我们还发现，非线性肌肉特性是负责显着减少能量消耗，他们也可以有助于波的速度差。这项工作是建立运动和其他行为的综合“整体动物”模型的一般计划的关键一步，这也将使我们能够将本体感受和外感受神经反馈结合起来。这种集成模型有助于我们理解生命系统如何工作，并有助于机器人系统的进一步发展。
Locomotion provides superb examples of cooperation among neuromuscular systems, environmental reaction forces, and sensory feedback. As part of a program to understand the neuromechanics of locomotion, here we construct a model of anguilliform (eel-like) swimming in slender fishes. Building on a continuum mechanical representation of the body as an viscoelastic rod, actuated by a traveling wave of preferred curvature and subject to hydrodynamic reaction forces, we incorporate a new version of a calcium release and muscle force model, fitted to data from the lamprey Ichthyomyzon unicuspis, that interactively generates the curvature wave. We use the model to investigate the source of the difference in speeds observed between electromyographic waves of muscle activation and mechanical waves of body curvature, concluding that it is due to a combination of passive viscoelastic and geometric properties of the body and active muscle properties. Moreover, we find that nonlinear force dependence on muscle length and shortening velocity may reduce the work done by the swimming muscles in steady swimming. In this article we develop a computationally tractable model for swimming in animals such as eels, lampreys, and aquatic snakes. The model combines motoneuronal activation, muscle dynamics, passive elasticity and damping in the spinal cord and body tissues, and simplified hydrodynamic reaction forces, thus allowing us to probe how neuromechanical interactions give rise to body shapes and, ultimately, motion through the water. We use it to investigate the sources of an interesting experimental observation in freely swimming fish: that waves of curvature propagating along the body lag behind and travel more slowly than the muscular activation waves measured by electromyography. By selectively “lesioning” components of the model, we deduce that the speed difference, at least in this type of fish, is largely due to passive viscoelasticity and body geometry. We also find that nonlinear muscle properties are responsible for a significant reduction in energy expenditure and that they can also contribute to the wave speed difference. This work is a key step in a general program to build integrated “whole animal” models of locomotion and other behaviors that will also allow us to incorporate proprioceptive and exteroceptive neural feedback. Such integrated models can contribute both to our understanding of how living systems work and to the further development of robot systems.
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DOI：
10.1098/rstb.1999.0441
发表时间：
1999-05-29
期刊：
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES B-BIOLOGICAL SCIENCES
影响因子：
--
作者：
Ekeberg, Ö;Grillner, S
通讯作者：
Grillner, S
DOI：
10.1098/rspb.1938.0050
发表时间：
1938-10-01
期刊：
PROCEEDINGS OF THE ROYAL SOCIETY SERIES B-BIOLOGICAL SCIENCES
影响因子：
--
作者：
Hill, AV
通讯作者：
Hill, AV
影响因子：
1.9
作者：
COHEN, AH;HOLMES, PJ;RAND, RH
通讯作者：
RAND, RH
影响因子：
1.9
作者：
BOWTELL, G;WILLIAMS, TL
通讯作者：
WILLIAMS, TL
影响因子：
2.5
作者：
COLEMAN, BD;DILL, EH;TOBIAS, I
通讯作者：
TOBIAS, I